Boat with ferro-concrete hull



Jain.4 27, -1970 M.J.'DEMo BOAT WITH FERRO-CONCRETE HULL I 3 Sheets-Sheet 1 Filedl March 13, 196s ETV l L Jan. 2.7, 1970 M. J. DEMO 3,491,711

' BOAT WITH FERRO-CONCRETE HULL Filed March 15, 1958 5 Shets-Sheet 2 Jan. 27, 1970 M. J. DEMO 3,491,711

BOAT WITH FERRO-CONCRETE HULL Filed March 13, 1958 5 Sheets-Sheet 5 INVENTOR. 444x Jf/wa lrraewfys United States Patent Olice Patented Jan. 27, 1970 ABSTRACT OF THE DISCLOSURE A boat formed with a metal mesh and metal rod rein- -forced concrete hull which, in horizontal cross section, is of general pumpkin seed configuration to provide stability and spaciousness. Projecting outwardly from opposite sides of the hull is a pair of sponsons extending lengthwise between the bow and stern. Portions of the sponsons extending forwardly from the stern are arranged in coplanar relationship with a flat bottom of the hull, these sponson portions coupled 4with the ilat bottom serving as a planing surface. The forward ends of the sponsons converge and curve upwardly to the bow. Independently angularly adjustable trim fins are positioned in recesses in the sponsons. The boat is propelled and steered by dual water jets symmetrically disposed on opposite sides of the longitudinal axis at the stern.

BACKGROUND OF THE INVENTION Field of the invention (l) This invention relates to concrete boats and more Specifically to a reinforced concrete planing boat of general pumpkin seed configuration equipped with sponsons, the boat being constructed to provide adequate speed and superior stability, spaciousness and comfort.

(2) The general concept of employing reinforced concrete to construct boat hulls is known in the boat building industry (e.g., U.S. Pat. 1,342,408 to Ianni, U.S. Pat. 2,321,811 to Harris). Reinforced concrete hulls are durable, reproo'f, water-proof, virtually corrosion and maintenance free, and become strengthened as time elapses. Other advantages over hulls constructed of customary materials are that concrete hulls have a higher strength to weight ratio than steel, are often less expensive and, especially in the larger boat sizes, are often lighter than vessels constructed of conventional materials such as wood. Existing hulls may incorporate a pair of bilge keels which in cooperation with a plurality of intermediate keels serve to reduce undesirable rolling and pitching movements of the boat in rough Waters (e.g., U.S. Pat. 2,550,298 to Romero and U.S. Pat. 3,267,898 to Evans). Ship `builders have also equipped boats with horizontal trim fins for counteracting or controlling undesired pitching and rolling motions (e.g. U.S. Pat. 2,409,040 to Harris and U.S. Pat. 3,015,298 to Bell et al.).

In addition to stabilizing boats by equipping them with keels and ns, another approach has been to modify the overall hull configuration. Boats of circularly shaped hulls with flat bottoms have been built to provide maximum volume and great resistance to undesired movements generated by rough waters and intense winds. Although extremely stable, such boats proved slow, ungainly and diicult to steer. In order to minimize the serious disadvantages and yet retain some of the advantages of circularly shaped boats, a modified boat has been constructed of generally pumpkin seed shape. As compared with conventional shapes, the ratio of beam to draft as well as its ratio of beam to longitudinal length were much larger. Vessels of this kind are very roomy and more maneuverable than circularly shaped vessels.

Various approaches have been taken to form boat hulls with planing surfaces to 'facilitate planing or skimming of the boat over a water surface. In one aspect the present invention improves on these constructions by arranging a pair of side sponsons extending lengthwise of the hull and cooperating with a flat bottom of the hull to provide a planing surface.

The present invention, as shall be fully described, combines some of these above described ship building concepts with additional concepts to achieve a unique and superior boat construction capable of being employed for a broad range of purposes. f

SUMMARY OF THE INVENTION The present invention comprehends a stable, spacious, and safe boat propelled by dual water jets capable of forcing the boat to skim or plane over the water surface. The boat hull is constructed from concrete reinforced with steel rods and multiple layers of steel mesh. The hull, as viewed from above, is of general pumpkin seed shape having side walls diverging from the bow to the beam point located between the midpoint of the longitudinal center line and the stern. From the beam point the sides converge toward one another and become joined to the stern. The hull has a larger ratio of beam to hull length than conventional vessels of equivalent length, the ratio being not substantially less than approximately 2 to 3. Projecting outwardly from the hull sides is a pair of symmetrically disposed spon-sons extending between the bow and stern. Portions of the sponsons extending f-orwardly from the stern are flat and arranged in a coplanar relationship with a Hat bottom of the hull. The bottom and under surfaces of the coplanar sponson portions constitute a planing surface on which the hull may plane or skim over the water surface. The forwardly disposed sponson portions curve upwardly toward the bow and serve to reduce water resistance and aid in lifting the hull to its planing position. Recesses are formed in the stern or intermediate sections of the sponsons, or both, to accommodate independently angularly adjustable ns for trimming the boat in roll and pitch. A pair of spaced, longitudinally extending skegs or keels depend from the flat bottom and serve the same function as a central keel or centerboard. The boat may be propelled by any desired propulsion means, specifically disclosed as dual water jets from turbine-driven pumps. Pivotally mounted over the jet discharge nozzles are deflectors that can be moved to reverse the jets so as to brake or reverse boat movement.

DESCRIPTION OF THE DRAWINGS The unique aspects and advantages of the present invention will be fully understood from the following detailed description in conjunction with the detailed drawings in which:

FIGURE l is a side elevational view of the concrete boat of the present invention.

FIGURE 2 is a rear elevational View of the boat of FIGURE l;

FIGURE 3 is a horizontal sectional view taken along line 3 3 of FIGURES 1 and 2 showing the pumpkin seed shape of the boat;

FIGURE 4 is a fragmentary, sectional view through the stern of the boat showing a propulsion unit for producing a water jet;

lFIGURE 5 is a fragmentary, perspective view of a typical side section of the boat showing the concrete side, bottom and sponson portions reinforced with steel bars and multiple layers of steel mesh.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, there is illustrated a boat 10 having a reinforced concrete hull 12 supporting a superstructure 18. As shown, superstructure 18 may be a typical cabin having a lower compartmentalized tier 21 located between a main deck 25 and an upper deck 29. Supported on upper deck 29 is an upper compartmentalized tier 31 sheltered by a suitably constructed roof 33. The particular shape and numbers of tiers of superstructure 18 may be modified to serve various purposes. It should be understood at the outset that boat is not restricted to any special use or use-s although it may furnish outstanding advantages Awhen used as a ferry boat for cargo and people, marine research vessel having an optional helicopter platform, luxury vessel, fishing expedition and sight-seeing vessel, etc. While hull 12 iS constructed from reinforced concrete, superstructure 18 may be constructed from lighter material such as wood, fiber glass, aluminum and other metals or any combination of these and other materials.

Hull 12 is formed with a generally transversely flat bottom 40 provides a shallow draft and merges at the opposite sides at 43 and 45 (referring to FIGURE 2) with generally vertical sidewalls 47 and 49. Depending from the at lbottom 40 is a pair of longitudinally extending and laterally spaced skegs or keels 51. The rearward extremeties of sidewalls 47 and 49, together with the rearward edge of bottom wall 40 are joined to a at transom or stern wall 55. As shall be explained in conjunction with FIGURE 3, the lateral distance between sidewalls 47 and 49 increases from stern 55 to a maximum distance (i.e., at the beam) and then diminishes as the sidewalls converge and eventually meet at the bow 58.

The spaced skegs 51 perform the usual function of a central keel or centerboard in preventing skidding and rotation of the boat and maintaining its movement parallel to its longitudinal axis.

Projecting laterally outwardly from sidewalls 47 and 49 at their junctions 43 and 45 with the hull bottom are a pair of sponsons 61 and 63, respectively, which extend lengthwise between bow 58 and stern 55. Sponsons 61 and 63 are symmetrical with respect to the hull longitudinal axis and have flat bottoms with their main portions 65 coplanar with the at bottom 40. As best shown in FIGURES l and 3, the sponson portions 66 extending forwardly of the flat main portions 65 converge and curve upwardly, eventually terminating adjacent one another at the bow 58. In addition to stabilizing the boat from rolling movements the ilat main sponson portions 65 enlarge the planing surface including the at bottom 40. As boat 10 is accelerated by the water jets (to be described) hull 12 is dynamically lifted until the hull is skimming or planing substantially on the water surface on flat bottom 40 and the at undersurfaces of the main sponson portions 65. The curved portions 66 of the sponsons are contoured so as to minimize water resistance and assist the lifting of hull 12 to its planing position.

Recesses are formed in the rearward and intermediate portions of sponsons 61 and 63 to receive trim fins 81, 82, 83 and 84. The fins are hinged to pivot pins and are angularly adjustable by actuators 85. Each actuator 85 may be independently operated from a common control point to trim the boat both in roll and in pitch and to vary its attitude so as to promote planing. In some embodiments only one pair of opposite ns may accomplish the desired results.

Hull 12 is an integral reinforced unit characterized by a pattern of bulkheads and other support elements, joined together to furnish a structural frame of a strength to enable hull 12 to withstand all anticipated impact and deformation'forces. Extending longitudinally rearwardly from bow 58 is a central vertical bulkhead 71 joined to a transverse vertical bulkhead 73 which is joined at its two ends to the sidewalls 47 and 49. Extending between transverse bulkhead 73 and stern 55 is a pair of spaced side bulkheads 75 and 76, respectively. As many other longitudinally extending bullheads 78 and cross bulkheads 79 are included as are necessary to furnish the desired strength and rigidity. The resulting compartments may be used as staterooms, fuel tanks,'galleys, labora# tories, storage Zones, etc. Extending upwardly from the oor built on`flat bottom 40 are stairways 91 and 93 leading to hatches (not shown). Stairway 93 allows access to an engine room 94 where dual propulsion systems 95 are mounted.

A typical fragmentary section from one of the sides of hull 12, as shown in FIGURE 5, is characterized by cement-sand mix concrete'96 embedding primary reinforcing steel rods 97 having web reinforcement` steel elements 98 welded thereto. Multiple layers of steel mesh 99 are laced together on opposite sides of rods 97 and elements 98 and are likewise bonded to the concrete 96. Although the present invention is not concerned lwith any special technique for casting, shaping or otherwise fabricating the reinforced concrete hull, the use of multiple layers of steel mesh is preferred as contributing to ilexibility of the hull by which it withstands terric impacts without cracking. A suitable ship building approach would involve forming a skeleton of the hull with the reinforcing rods, cross elements and layers of wire mesh, applying mortar by hand or machine from the inside of the hull skeleton, forcing it through the mesh and then smoothing the mortar from the outside.

By shaping hull 12 into a pumpkin seed configuration in horizontal section, boat 10 is much more spacious than conventional vessels of comparable length, and highly lstable and safe. The term pumpkin seed shaped is intended to describe a hull whose port and starboard sides gradually diverge from the bow to the beam and then converge less gradually toward the stern, the ratio of beam to longitudinal hull length being larger than that of conventional boats of equivalent length. For purposes of example only, the overall hull length'may be 150 and the hull beam (i.e., widest breadth of the hull) 100', making the beam to length ratio 2 to 3. Preferably, as shown in FIGURE 3, the beam is located betweeny the stern and the midpoint of the hulls longitudinal axis.

Conventional dual propulsion .assemblies 95, one-of which is shown in FIGURE 4, are installed in the engine room for producing water jets to be ejected rearwardly, preferably below the water surface. Propulsion assembly 95 may include a conventional marine engine 101 that may be a diesel or gasoline reciprocating engine or a gas turbine. Air is drawn through intake duct 104 for mixture with fuel to achieve the desired combustion product, which, after its energy has been used to produce the desired mechanical motion, is discharged through exhaust duct 105. Engine 101 powers an output shaft 109 that operates a pump which draws water through an inclined inlet port 117. A water jet is ejected through a discharge nozzle 119 to generate thrust for propelling the boat. The jets give high thrust with shallow draft and the pair may be controlled to steer the boats direction.

Pivotally mounted on discharge nozzle 119 is a deflector 121 which during forward propulsion remains in a retracted position so as not to block the discharge nozzle. Deiiector 121 may be swung to a position reversing the direction of the jet to reverse or brake boat movement.

Although a particular embodiment has been chosen to best illustrate the unique features and outstanding advantages of this invention, it is to be understood that the scope of this invention is to be limited only by the following claims.

I claim:

1. A boat comprising:

a concrete hull of general pumpkin seed shape in horizontal section characterized by sides which diverge from the bow to the beam located between the stern and the midpoint of the hull longitudinal center line and converge from the beam to the stern, the hull having a ratio of beam to longitudinal length not substantially less than approximately 2 to 3.

2. The boat according to claim 1 further comprising:

plural layers of metal mesh embedded in the concrete to strengthen the hull while maintaining flexibility against impact.

3. 'lhe boat defined in claim 2 further characterized by concentrated reinforcement in the form of crossed metal rods embedded in the concrete.

4. The boat according to claim 1 further comprising: a pair of sponsons projecting outwardly from the hull side walls, the sponsons extending forwardly at the bottom of the hull from the lower portion of the stern to locations substantially forward of the beam from which they curve upwardly and terminate adjacent the upper portion of the bow.

5. The boat according to claim 4 further comprising:

a flat bottom formed on the hull; and

at bottoms on the sponson portions extending forwardly from the stern which are disposed in coplanar relationship with the flat bottom,'the flat sponson portions and at bottom constituting a planing surface.

`6. The boat according to claim 5 further comprising:

means forming recesses in the flat bottom sponson portions, and

stabilizing tins positioned in the recesses, each being pivotally mounted to the hull and angularly adjustable.

7. The boat dened in claim 6 and including:

at least one longitudinally extending skeg depending from the bottom of the hull.

8. The boat according to claim 7 further comprising:

a propulsion system mounted in the stern for producing at least one rearwardly directed water jet.

9. A boat hull comprising:

a flat bottom;

side walls joined at their lower ends to the at bottom,

a pair of sponsons projecting outwardly from the side walls and extending lengthwise between the bow and stern, said sponsons comprising:

lirst sponson portions extending forwardly from the stern in substantially coplanar relationship with the at bottom, the first portions and flat bottom constituting a planing surface, and

second sponson portions curving upwardly from said first portions and converging adjacent the bow, the second portions being shaped to assist in raising the hull to a planing position.

10. The hull according to claim 9 further comprising:

means forming recesses in the first sponson portions,

and

stablizing tins positioned in the recesses, each iin being pivotally mounted to the hull and independently angularly adjustable.

11. The hull according to claim 9 further comprising:

means forming recesses in the stern section and an intermediate section of the -first sponson portions;

stabilizing fins positioned in the recesses, each being pivotally mounted to the hull and independently angularly adjustable, and

at least one longitudinally extending skeg depending from the flat bottom.

12. The hull according to claim 9 wherein:

the hull is of general pumpkin seed shape in horizontal reinforced concrete.

References Cited UNITED STATES PATENTS 4/1921 Eagan 114-65 2/ 1922 Christiansen 114-63 FOREIGN PATENTS 329,812 12/1920 Germany.

ANDREW H. FARRELL, Primary Examiner U.S. C1. X.R. 

